zondag 22 december 2013

America's cup gyro control revealed

 COPY of cupexperience.com

Super clear explanation of the control system, thanks!

remains of the question what this all really means and what are the limits, just generating power by humans, which is then used by machinery/eklectronics to controll the beast (and next, to drive it?) Interesting question is when sailing stops and becomes motorsports ....

AC72 foil control secrets

Some people have questioned whether Oracle Team USA had a secret (and illegal) foil control system in their AC72 that helped them defend the America's Cup.
OTUSA has released drawings and photos of their system, which used a simple "mechanical feedback" loop to allow precise control of the daggerboard rake. Helmsman Jimmy Spithill had buttons on the wheel to rake the daggerboard fore and aft in precise increments of 0.5° giving him better control over lift for hydrofoiling.
OTUSA designers Dimitri Despierres (mechanical systems) and Eduardo Aldaz Carroll (electronic systems) began work in late June 2013 to help the team gybe better. The goal was to reduce distance lost in a gybe from 150 meters to 30 meters. To do this the engineers needed to deal with the problem that board movement varied depending on hydraulic pressure, making it impossible to control lift. What they needed was a way to move the board a fixed amount independent of the pressure and drag load on the board. Within a month, mechanical engineer Alex Davis developed a test bench with a servo control, hydraulic valve and hydraulic ram to simulate movement of the daggerboard box (see photo below).
Once the test bed system worked, the system was tested on board. Accuracy was fine, but it reacted too slowly. Mechanical engineer Neil Wilkinson and hydraulics specialist Rolf Engelberts improved the system to improve response speed and make everything more reliable and robust.

Windturbine sailing

Sailing straight into the wind is possible with  windturbine/windmill propulsion.
The turbine is mostly directly mechanically coupled to the propellor.
Her are some examples to get you inspired?

zaterdag 7 december 2013

Nuvinci continous bicycle transmission

Fallbrook technologies have invented a very interesting continuos variable bicycle drive.

As far as I am concerned there are two very clever bits:
- using canting ball to transmit power and change drive ratio.
- using a compressable liquid  to assist in this powertransmission.

Have a look at the pictures and their website.